The arrests, as part of Operation Unmask, apparently occurred in Spain, Argentina, Colombia and Chile and are related to cyber attacks primarily in Columbia and Chile. Around 250 items of IT equipment and mobile phones were seized during co-ordinated searches of 40 premises in 15 cities. “The Internet cannot be seen as a safe haven for criminal activity,” commented Bernd Rossbach, acting Interpol executive director of police services.

Among those arrested were four alleged members in Spain, ten in Argentina, six in Chile and five in Colombia. The Spanish arrests were apparently for attacks against the websites of Spanish political parties, and included the alleged manager of Anonymous operations in Spain and Latin America (known on the internet as ‘Thunder’ and ‘Pacotron’). The Spanish police also said that two servers in Bulgaria and the Czech Republic had been blocked as part of the operation. Those arrested in Spain face prison sentences of up to five years if convicted.

The precise details of how many arrests took place in which countries are confused. The Associated press is reporting that “Gen. Carlos Mena, commander of Colombia's Judicial Police, said no one was arrested in Colombia... ‘You have to leave them alone, so when we have all the evidence, and the prosecutor makes the decision, we will be all over it and capturing them,’ he said.” A reasonable assumption, then, is that ‘Operation Unmask’ is continuing, and that further arrests are likely to be made. It is probable that the confiscated equipment will also indicate more suspects.

Javier Merchan, communication co-ordinator at Panda Security (a company with experience in working with the Spanish police against cybercriminals, notably in taking down the Mariposa botnet) told Infosecurity that the Spanish arrests “are connected with attacks on Spanish political party websites, defacing websites, publishing data about police assigned to the royal family and some members of the government and carrying out denial of service attacks.” He added that two of the arrested are being held in prison under court order, one is on bail and the fourth, a minor, is in custody. But although the charges carry prison sentences, Merchan suspects that all four will be released, especially if this is a first offense. “These three charges can lead to jail, but they probably will be released free, even if the police can prove they carried out all the charges.”

Anonymous apparently responded by attacking Interpol’s main site. Comments on Twitter suggested that it had been ‘taken down’, and the UK’s Guardian reported the “website went down briefly on Tuesday”. At the time of writing this report there was no discernible delay in accessing the site. The strength and weakness of Anonymous is that according to its own members it is less an organization and more an idea. Rapid response such as the attack on Interpol is likely to be more emotional than organized. However, given Anonymous’ increasing politicization and tendency to target law enforcement in ‘revenge’ attacks it is reasonable to expect a more serious response over the next few weeks.